A five stage chopper stabilized instrumentation amplifier using feedforward compensation

A programmable gain chopper stabilized instrumentation amplifier is presented. It uses a fifth order amplifier architecture with simulated open loop gain of 200 dB. It is the first reported silicon implementation of an amplifier using multipath feedforward compensation. The instrumentation amplifier achieves noise density of 7 nV/sqrt(Hz) and THD of -110 dB with 14 mW from a single 5 V supply. It is implemented in 0.6 /spl mu/m CMOS and has an active area of 4 mm/sup 2/.